Selectively-acting fuse



J. B. SEMPLE.

SELECTIVELY ACTING FUSE. APPLICATION FILED OCT. 16. 1919.

1,347,716, Patented July 27,1920.

PATENT OFFICE.

JOHN B. SEMPLE, OF SEWIGKLEY, PENNSYLVANIA.

SELECTIVELY-ACTING FUSE.

To all whom it may concern Be it known that I, JOHN B. SEMPLE, residing a-t Sewickley, in the county of Allehen and State of Pennsylvania, a citizen of the United States, have invented or discovered certain new and useful Improvements in'Selectively-Acting' Fuses, of which improvements the following is a specification.

communication of i sion cap, through t invention relates to improvements in and consists in a selectively a fuse which, 1n

y fuses for shells, acting fuse: that is to say, case the shell makes impact upon a body relatively small resistance to penetration, functions to effect bursting quickly, but which, in case the shell makes impact upon a body of great resistance to enetration, such as heavy armor plate, with relative slowness.

The accompanying drawing shows in longitudinal section a fuse embodying my invention.

In this drawing the fuse stock is indicated at 1, and is, as will be seen, adapted to be screwed into an opening in the base of a shell. an anyil' adaptiid to move, in a runway which of the structure. In this instance it is the hammer block which alone is movable, and it takes the familiar form of a, plunger equipped with a firing-pin. A shear-pin/l provided, normally holding the movable member against movement; but the shearpin is relatively weak, so that," under the tremendous shock of firing, the movable member first sets back, under inertia, shearing the pin in so doing and releasing itself, and then, when subsequently the shell makes impact, the movable member will drive forward, un'der inertia, and ex lode the percussion'cap. A spring 5 is e ective, to prevent the movable member, when once 1t is released, from moving forward until under the great and sudden retardation which occurs on impact, the movable member lunges forward with great relative momentum, compressing the spring as it goes, and striking andfirmg the rcussion cap. All this is well known in t e art.

My present invention has to do with the 'ition from the ercuse block which lies between, and to the burster charge. The block is in this case the anvil block 2; but, in this block 2 and a hammer block 3 one relatively to the other,

Specification of Letters Patent.

Wlll function This stock is provided within withextends longitudinally v upon a Patented July 27, 1920.

Application filed October 16, 1919. Serial No. 331,087.

connection, it will be borne in mind that anvil and hammer members may be reversed in position if desired, as already intimated, and as is known to the art. Communication is direct through block 2 to the burster charge.

There are through block 2 two lines through which ignition may be communicated; one of these. is the flashway 67 the other is the canal 6-8, in the course of which is'set a pellet 9 of slow-burning material, such as is commonly used in time fuses. If ignition passes through the flashway 6-7, the action of the fuse 1s quick, and bursting follows at a minimum time interval after impact; if on the other hand ignition is through canal 68, then the pellet 9 of slow-burning material must be burned through before ignition can reach the burster charge, and this will any case very short, of course) may be varied, increased or decreased, according to the composition of pellet 9, the degree 0 its compression in manufacture, A duct 18 aflords escape for gases generated by the burning of pellet 9.

It remains now to explain how the fuse is rendered selective, to the end that on impact body offering relatively small resistance to penetration, ignition is through 6-7, and on impact upon a body offering relativelyv great resistance to penetration, ignition is throu h canal 6- 8.

In the course of the' ashway 6-7 is a chamber 10, with a plug 11 in it, constituting a movable cut-off for the flashway. This plug is formed of rigid material-steel, for example,-an d is imperforate. Normally, this plug is in the retracted position shown, leaving the flashway unobstructed, and held in this position -by a shear-pin 12. It

' will be observed, first, that the plug is norbe accomplished only after an appreciable time interval following impact. The length of this time interval (in.

and its length.

11 sets forward to obstruct flashway 67. It will be observed that as shown in the drawings the distance through which plug 11 advances to close the flashway is very much less than that through which plunger 3 advances to fire the percussion cap, and it is of the essence of the invention that the plug 11 when it functions shall in closing the flashway anticipate the flash.

The canal 6-8 through which delayed ignition may be effected is always in operative condition, and ignition proceeds along that line; but, as will now be well understood, in case the ercussion cap is fired without operation of cut-oif plug 11 (which will happen on impact upon relatively light resistance), the progress of ignition through canal 68 will be anticipated by the flash which travels directly through ,flashway.

67 to effect quick firing of the burster charge. On the other hand, heavy armor has caused plug 11 to close the flashway before the percussion cap is fired, then the only remaining line of ignition is through delay pellet 9,.and so the fuse has become a delay-action fuse.

17isa if impact upon,

booster charge, intermediate in between percuse; it is fired by in turn imparts detonation to the burster charge beyond. It

1s a member of the/assembly already well known in many forms to the art; and in and of itself it constitutes no part of my present invention.

I claim as my invention:

A selectively acting fuse fora projectile includin a block in which are formed two paths 0 ignition transmission from percussion cap to burster charge, one of said paths being a quick-action and the other a delay-action path, a rigid imperforate plug, under all lesser strains immovable and aside from either path of ignition transmission, but under the strain of impact upon heavy armor movable within the block to a position of closure of said quick-action ignition path, substantially as described.

In testimony whereof I have hereunto set my hand.

JOHN B. SEMPLE. Witnesses:

v BAYARD H. CHRITTY,

FRANCIS J. TOMASSON. 

